Strange memory maps!

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Brendan
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Strange memory maps!

Post by Brendan »

Hi,

Ok, here's the strangest memory map I've seen:

Code: Select all

0x000000000 to 0x00009DFFF -     632 KiB, usable RAM
0x00009E000 to 0x00009FFFF -       8 KiB, system
 * legacy hole (256 KiB) *
0x0000E0000 to 0x0000FFFFF -     128 KiB, system
0x000100000 to 0x0CE72FFFF - 3381440 KiB, usable RAM
0x0CE730000 to 0x0CE7F2FFF -     780 KiB, ACPI NVS
0x0CE7F3000 to 0x0CFA91FFF -   19068 KiB, usable RAM
0x0CFA92000 to 0x0CFA93FFF -       8 KiB, system
0x0CFA94000 to 0x0CFB8DFFF -    1000 KiB, usable RAM
0x0CFB8E000 to 0x0CFBE4FFF -     348 KiB, ACPI NVS
0x0CFBE5000 to 0x0CFBE6FFF -       8 KiB, usable RAM
0x0CFBE7000 to 0x0CFBF1FFF -      44 KiB, ACPI reclaimable
0x0CFBF2000 to 0x0CFBF2FFF -       4 KiB, usable RAM
0x0CFBF3000 to 0x0CFBFEFFF -      48 KiB, ACPI reclaimable
0x0CFBFF000 to 0x0CFBFFFFF -       4 KiB, usable RAM
0x0CFC00000 to 0x0CFFFFFFF -    4096 KiB, system
 * PCI hole (524288 KiB) *
0x0F0000000 to 0x0F7FFFFFF -  131072 KiB, system
0x0FFF00000 to 0x0FFFFFFFF -    1024 KiB, system
0x100000000 to 0x22BFFFFFF -    4800 MiB, usable RAM
That's 2 ACPI reclaimable areas, 2 ACPI NVS (Non-Volatile Storage) areas, and 8 separate RAM areas! :D

This is from a relatively modern Intel machine - an Intel DG33FB/DG33BU motherboard with an Intel BIOS. I used "BIOS Int 0x15, eax = 0xE820" to get the memory map, and thought it might be interesting for others to see how messed up it can get.

I was also wondering if anyone has a computer with an even stranger memory map - post yours if it looks unusual! :)


Cheers,

Brendan
For all things; perfection is, and will always remain, impossible to achieve in practice. However; by striving for perfection we create things that are as perfect as practically possible. Let the pursuit of perfection be our guide.
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sawdust
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Re: Strange memory maps!

Post by sawdust »

I would guess that the system bios is buggy.
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froggey
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Re: Strange memory maps!

Post by froggey »

Code: Select all

[    0.000000]  BIOS-e820: 0000000000000000 - 000000000008f000 (usable)
[    0.000000]  BIOS-e820: 000000000008f000 - 00000000000a0000 (reserved)
[    0.000000]  BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
[    0.000000]  BIOS-e820: 0000000000100000 - 00000000ceea6000 (usable)
[    0.000000]  BIOS-e820: 00000000ceea6000 - 00000000cef1d000 (ACPI NVS)
[    0.000000]  BIOS-e820: 00000000cef1d000 - 00000000cfd84000 (usable)
[    0.000000]  BIOS-e820: 00000000cfd84000 - 00000000cfd8c000 (reserved)
[    0.000000]  BIOS-e820: 00000000cfd8c000 - 00000000cfe2b000 (usable)
[    0.000000]  BIOS-e820: 00000000cfe2b000 - 00000000cfe2f000 (reserved)
[    0.000000]  BIOS-e820: 00000000cfe2f000 - 00000000cfea9000 (usable)
[    0.000000]  BIOS-e820: 00000000cfea9000 - 00000000cfeac000 (ACPI data)
[    0.000000]  BIOS-e820: 00000000cfeac000 - 00000000cfef0000 (ACPI NVS)
[    0.000000]  BIOS-e820: 00000000cfef0000 - 00000000cfef2000 (ACPI data)
[    0.000000]  BIOS-e820: 00000000cfef2000 - 00000000cfef3000 (usable)
[    0.000000]  BIOS-e820: 00000000cfef3000 - 00000000cfeff000 (ACPI data)
[    0.000000]  BIOS-e820: 00000000cfeff000 - 00000000cff00000 (usable)
[    0.000000]  BIOS-e820: 00000000cff00000 - 00000000d0000000 (reserved)
[    0.000000]  BIOS-e820: 00000000fff00000 - 0000000100000000 (reserved)
[    0.000000]  BIOS-e820: 0000000100000000 - 0000000130000000 (usable)
From my Intel D975XBX2, also with an Intel BIOS.
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